Long ago, there lived in Greece a learned man. He was so well-known{#blank#}1{#/blank#}his knowledge of almost everything that lots of people from all over the country came to learn from him. The great man{#blank#}2{#/blank#}(teach) his students whole-heartedly and answered their questions with great{#blank#}3{#/blank#}(patient).

    One day, a student asked him, “My dear teacher, didn't you say you yourself have many more questions about things than we do?{#blank#}4{#/blank#}I think we students have far more than you.”

    With a smile on his face, the teacher drew two circles, one as large as a big cake, the other smaller. Then he said, “Of course, I have learned much more. But it is wrong{#blank#}5{#/blank#}(think) a teacher has fewer questions than his students. Now, look at these two circles. The inside of the{#blank#}6{#/blank#}(big) one is my knowledge of things, and the inside of the smaller one is{#blank#}7{#/blank#}(your). Out of the circles is what is still unknown to us. Since mine is larger, I have to use the longer line to draw the bigger circle. That means I have more opportunities to face something{#blank#}8{#/blank#}(know). And that's{#blank#}9{#/blank#}I myself have more questions than you do. The{#blank#}10{#/blank#}(much) you learn, the more questions you have. You will never learn enough, you know.”

    With the rapid development of the Internet, more and more teenagers make friends online nowadays. Some people say it's good to do that, while others think it's {#blank#}1{#/blank#}(harm) especially to school pupils.

    Some consider that making friends online is a modern way to share friendship {#blank#}2{#/blank#} others. They can express their thoughts {#blank#}3{#/blank#}(free) to improve social skills and fluency in English. On the contrary, some strongly believe it is {#blank#}4{#/blank#} waste of time to make friends through online communication and what's worse, those so-called "friends" are likely to cheat you after {#blank#}5{#/blank#}(gain) your trust.

    In my opinion, {#blank#}6{#/blank#}the Internet is good or not depends on how we use it. If it {#blank#}7{#/blank#}(use) properly, we can communicate with people {#blank#}8{#/blank#} come from every corner of the world, and share life experiences. Of course, however, since the Internet was born, many bad men {#blank#}9{#/blank#} (make) use of it to do something bad. So we must learn to determine true or false and avoid being hurt.

    In conclusion, every coin has two {#blank#}10{#/blank#} (side). So does the Internet. If used in a proper way, the Internet has more advantages in seeking friendship.

    While not everyone will have pondered (思索) the subject while staring out of the window during {#blank#}1{#/blank#} flight, the question as to why aeroplanes have circular windows rather than square ones is interesting.

    Over the years, aerospace engineering {#blank#}2{#/blank#} (make) huge leaps in aeroplane technology, meaning planes can carry {#blank#}3{#/blank#} passengers and go faster. The planes have also changed shape to increase safety — including the windows.

    In the 1950s, {#blank#}4{#/blank#} jetliners were starting to become mainstream, the De Havilland Comet came {#blank#}5{#/blank#} fashion. With a pressurised cabin, it was able to go higher and faster than other aircraft.

    {#blank#}6{#/blank#}, the plane had square windows and in 1953 two planes fell apart in the air, {#blank#}7{#/blank#} (kill) 56 people in total.

    The reason for the {#blank#}8{#/blank#} (crash)? The windows.

    {#blank#}9{#/blank#} there's a corner, there's a weak spot. Windows, having four corners, have four potential weak spots, making them likely to crash under stress — such as air pressure.

    By curving the window, the stress that would {#blank#}10{#/blank#} (eventual) crack the window corner is distributed and the likelihood of it breaking is reduced.